To achieve an optimum of efficiency in modern automotive and large stationary diesel engines, the prior art of fuel management employs several types of engine and environment condition sensing devices. Such sensing devices include, manifold absolute and barometric pressure, coolant temperature as well as distributor input rpm and throttle position sensing transducers. In many cases, the aforesaid devices are linked to a computer acting as an information processor between a set of inputs and a set of outputs. The purpose of which is to continuously monitor and readjust an engine to ever changing environmental and driving conditions. Manifold pressure and engine inlet temperature sensing transducers are some of the more commonly used devices. Most engines tolerate a wide range of fuel/air mixture. However, due to changing engine loads, fuel quality and environmental conditions, the engine must continuously be re-adjusted to achieve optimum engine performance. To assure the correctly proportioned stoichiometric air/fuel ratio of 15 lb of air to 1 pound of fuel, fuel-injected and supercharged engines require the employment of an air mass-flow sensing transducer to compensate for drastic changes in manifold pressure and temperature while operating at changing environmental conditions. The existing state of art however, includes no practical method for making single transducer measurements on the mass-flow rate of air while passing through an engine. In the prior art of fuel management, obtaining the mass-flow rate of air at a given density requires the calculating of the effects of temperature and pressure on the volume of the air. Although, in some devices of the prior art the venturi action of a carburetor in conjunction with separate manifold and barometric pressure as well as temperature sensing transducers, produces approximately correct air/fuel mixture. In other systems of the prior art, the amount of air passing through a particular engine may be determined by a computer, calculating the volume of air being drawn into the engine cylinders at a given engine speed. This takes into account the volumetric efficiency factor for the particular engine along with moment to moment barometric pressure, engine coolant, atmospheric temperature and other readings taken by the various engine connected sensors. Still other systems compute the rate of heat transfer from a heated wire or a heated surface to the engine induced air in conjunction with other engine and environment condition sensing devices in order to determine the amount of air passing through an engine at a given time. Multiple transducer systems designed to obtain the mass-flow rate of a gas at frequent changes in pressure and temperature conditions however, are too costly for use in automotive applications.